Unlike Facebook and Google, which let employees publish their academic breakthroughs in scientific journals and on blogs, Apple prevents its staff from talking about their research both online and offline. They're allowed to attend conferences but they don't give talks about what Apple is working on and they generally only disclose their employer when they're asked to.

This approach could be hindering the company's ability to hire some of the world's smartest minds, based on what Facebook AI director Yann LeCun said last week.

Describing how he gets the most talented software engineers in the world to come and work on Facebook's AI efforts, LeCun said: "Offering researchers the possibility of doing open research, which is publishing their work.

"In fact, at FAIR [Facebook Artificial Intelligence Research], it's not just a possibility, it's a requirement," he said in London. "So, [when] you're a researcher, you assume that you're going to publish your work. It's very important for a scientist because the currency of the career as a scientist is the intellectual impact. So you can't tell people 'come work for us but you can't tell people what you're doing' because you basically ruin their career. That's a big element."

Apple's secrecy was cited by Bloomberg last October as something that's holding back the company's AI development efforts.

"Apple is off the scale in terms of secrecy," Richard Zemel, a professor in the computer science department at the University of Toronto, told Bloomberg. "They're completely out of the loop."

Despite being a highly secretive company, Apple was still able to hire Carnegie Mellon University's (CMU) Russ Salakhutdinov, one of the world's leading talents in AI, as director of AI research. Although Salakhutdinov works for Apple, he still holds his position at CMU. This suggests that Apple is willing to let some of its staff remain a part of the academic community, providing they don't talk about what they do for the iPhone maker.

Apple declined to comment.

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